A backlink refers to an incoming link to a web page. Whenever a web page links to another site or any other page, it is called a backlink. A web page that has a lot of backlinks tends to rank higher on search engines.

The are several ways you can check the backlinks of a website:

LinkDiagnosis.com – A free tool which uses Firefox to check the backlinks of a website. Simply open linkdiagnosis.com with Firefox and then install the plugin for Firefox as per the instructions listed on the site. Then type in the name of your website and linkdiagnosis.com will find the sites that link back to yours. As with any of these tools, linkdiagnosis.com will not give you 100% of the sites that link back to you but it will give you a good representation.

Ahrefs.com – This is an easy tool to use and comes with a free version. Go to ahrefs.com and sign up for an account. You do have to register to use this tool but payment is not required. With your account open, use the Site Explorer to type in a domain name and see what comes up. This tool will allow you to see the backlinks coming to a specific page. If you upgrade your account with a subscription you will be able to see who is linking to you or your competitor’s site.

Majestic SEO – This tool will give you limited information on backlinks to your site or that of your competitor. Once you register, you can run reports on your site for free but you must verify ownership. Create a verification file and allow their bot/spider to go through your site. You will need to pay to run in-depth reports on a competitors site. For around $50 per month, you can run up to 60 in-depth reports.

Google Webmaster Tools – This is another great free way to obtain backlinks data. Google Webmaster Tools will provide a highly detailed list of the sites that link back to yours, however, you can only use it on sites that you own or control. To verify your site, you will need to upload a file or a piece of code and so you cannot use this tool to check the backlinks of a competitor.

Checking your backlinks every so often is a useful tool and can help you reach your goals by determining whether you’ve met your link building goals for each and every campaign you set out on.